This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. There is a readily recognizable PNPase-like molecule in the human genome, which localizes to mitochondria, and its deficiency leads to mitochondrial dysfunction. Importantly, we have found a direct interaction between recombinant SUV3 and PNPase in vitro. We plan to further examine their interaction in detail to test whether SUV3 works in concert with PNPase in monitoring mitochondrial RNA degradation. Are there other proteins in the degradosome together with SUV3/PNPase? If yes, what are their roles in RNA degradation? Isolating and identifying the SUV3/PNPase complex from mitochondria are critical steps to advance our current knowledge of the mammalian mitochondrial degradosome.